These three pillboxes still remain as a witness of the Spanish Civil War in a park of Madrid.

The morbid items in this small and hidden museum are not for the weak stomached.

An enchanting monastery in the Spanish countryside appears lifted from a fantasy tale.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

This chapel on a cliff is renowned for its healing powers and was founded on the site of a supposed divine intervention.

A hip bar decorated with walls of golden skulls.

This little museum is built on a theater that was once a wildly elaborate speakeasy.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

A small chapel celebrating the spiritual bond between dogs and humans.

This "common-as-dirt" museum celebrates the glory of normalcy.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

The oldest stone house in Paris was built by its most famous alchemist.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

France's most famous cemetery, with some of its most curious tombs.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

Traditional Appalachian dances such as the Georgia Rang Tang and the Shoo-Fly Swing are kept alive at this weekly event.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

For over 30 years the walls of this Harlem schoolyard have been a gallery of street art by "Kings and better."

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

Small museum packed with artifacts recovered by the man rumored to be the real-life inspiration for Indiana Jones.

The only recreation of William Shakespeare's indoor playhouse.

An architectural statement of artistic intent smack in the middle of Providence, Rhode Island's Colonial uniformity.